Modulite: a simple solution to a difficult problem

The effects of airway disease on the deposition of inhaled drugs

INTRODUCTION

The deposition of inhaled medications is the first step in the pulmonary pharmacokinetic process to produce a therapeutic response. Not only lung dose but more importantly the distribution of deposited drug in the different regions of the lung determines local bioavailability, efficacy, and clinical safety. Assessing aerosol deposition patterns has been the focus of intense research that combines the fields of physics, radiology, physiology, and biology.

AREAS COVERED

The review covers the physics of aerosol transport in the lung, experimental, and in-silico modeling approaches to determine lung dose and aerosol deposition patterns, the effect of asthma, chronic obstructive pulmonary disease, and cystic fibrosis on aerosol deposition, and the clinical translation potential of determining aerosol deposition dose.

EXPERT OPINION

Recent advances in in-silico modeling and lung imaging have enabled the development of realistic subject-specific aerosol deposition models, albeit mainly in health. Accurate modeling of lung disease still requires additional refinements in existing imaging and modeling approaches to better characterize disease heterogeneity in peripheral airways. Nevertheless, recent patient-centric innovation in inhaler device engineering and the incorporation of digital technology have led to more consistent lung deposition and improved targeting of the distal airways, which better serve the clinical needs of patients.

How to engineer aerosol particle properties and biopharmaceutical performance of propellant inhalers

Given the environmental compulsion to reformulate pressurised metered dose inhalers (pMDI) using new propellants with lower global warming potential, this study investigated how non-volatile excipients can be used to engineer aerosol particle microphysics and drug release. The dynamics of change in particle size, wetting and physical state were measured for single particles (glycerol/ethanol/beclomethasone dipropionate; BDP) in the aerosol phase at different relative humidity (RH) using an electrodynamic balance. BDP dissolution rates were compared for aerosols from pMDI containing different ratios of BDP:glycerol or BDP:isopropyl myristate (IPM). In 45 % RH, ethanol loss was followed by evaporation of condensed water to generate spherical particles with solid inclusions or compact irregular-shaped solid particles, according to the presence or absence of glycerol. In RH > 95 %, condensed water did not evaporate and BDP formed solid inclusions in water/glycerol or water droplets. Varying the non-volatile component, 0-50 % w/w, in pMDI resulted in a concentration-dependent 4-8-fold reduction in BDP dissolution rate. These findings demonstrate that non-volatile excipients provide a means of engineering aerosol properties and, modifying the rate of drug release from aerosol medicines. We also demonstrated differences between particles formed in vitro in ambient humidity versus higher humidity, more like that encountered during oral inhalation.

Extrafine HFA-beclomethasone-formoterol vs. nonextrafine combination of an inhaled corticosteroid and a long acting β2-agonist in patients with persistent asthma: A systematic review and meta-analysis

Objective

Airway inflammation in asthma involves not only the central airways but extends to peripheral airways. Lung deposition may be key for an appropriate treatment of asthma. We compared the clinical effects of extrafine hydrofluoroalkane (HFA)-beclomethasone-formoterol (BDP-F) versus equipotent doses of nonextrafine combination of an inhaled corticosteroid and a long acting β2-agonist (ICS-LABA) in asthma.

Methods

We identified eligible studies by a comprehensive literature search of PubMed, EMBASE and the Cochrane Central Register of Controlled Trials (CENTRAL). Data analysis was performed with the Review Manager 5.3.5 software (Cochrane IMS, 2014).

Results

A total of 2326 patients with asthma from ten published randomized controlled trials (RCTs) were enrolled for analysis. Change from baseline in morning pre-dose peak expiratory flow (PEF), evening pre-dose PEF and forced expiratory volume in one second (FEV₁) were detected no significant differences between extrafine HFA-BDP-F and nonextrafine ICS-LABAs (p = 0.23, p = 0.99 and p = 0.23, respectively). Extrafine HFA-BDP-F did not show any greater benefit in forced expiratory flow between 25% and 75% of forced vital capacity (FEF25-75%), the parameter concerning peripheral airways (MD 0.03L/s, p = 0.65; n = 877). There were no substantial differences between interventions in fractional exhaled nitric oxide (FeNO) levels or in its alveolar fraction. The overall analysis showed no significant benefit of extrafine HFA-BDP-F over nonextrafine ICS-LABA in improving Asthma Control Test (ACT) score (p = 0.30) or decreasing the number of puffs of rescue medication use (p = 0.16). Extrafine HFA-BDP-F did not lead to less exacerbations than nonextrafine ICS-LABA (RR 0.61, 95% CI: 0.31 to 1.20; I² = 0; p = 0.15).

Conclusion

Enrolled RCTs of extrafine HFA-BDP-F have demonstrated no significant advantages over the equivalent combination of nonextrafine ICS-LABA in improving pulmonary function concerning central airways or peripheral airways, improving asthma symptom control or reducing exacerbation rate.

Impact of extrafine formulations of inhaled corticosteroids/long-acting beta-2 agonist combinations on patient-related outcomes in asthma and COPD

Asthma and chronic obstructive pulmonary disease (COPD) are among the most common chronic diseases worldwide, characterized by a condition of variable degree of airway obstruction and chronic airway inflammation. A large body of evidence has demonstrated the importance of small airways as a pharmacological target in these clinical conditions. Despite a deeper understanding of the pathophysiological mechanisms, the epidemiological observations show that a significant proportion of asthmatic and COPD patients have a suboptimal (or lack of) control of their diseases. Different factors could influence the effectiveness of inhaled treatment in chronic respiratory diseases: patient-related (eg, aging); disease-related (eg, comorbid conditions); and drug-related/formulation-related factors. The presence of multiple illnesses is common in the elderly patient as a result of two processes: the association between age and incidence of degenerative diseases; and the development over time of complications of the existing diseases. In addition, specific comorbidities may contribute to impair the ability to use inhalers, such as devices for efficient drug delivery in the respiratory system. The inability to reach and treat the peripheral airways may contribute to the lack of efficacy of inhaled treatments. The recent development of inhaled extrafine formulations allows a more uniform distribution of the inhaled treatment throughout the respiratory tree to include the peripheral airways. The beclomethasone/formoterol extrafine formulation is available for the treatment of asthma and COPD. Different biomarkers of peripheral airways are improved by beclomethasone/formoterol extrafine treatment in comparison with equivalent nonextrafine inhaled corticosteroids/long-acting beta-2 agonist (ICS/LABA) combinations. These improvements are associated with improved lung function and clinical outcomes, along with reduced systemic exposure to inhaled corticosteroids. The increased knowledge in the pathophysiology of the peripheral airways may lead to identify specific phenotypes of obstructive lung diseases that would mostly benefit from the treatments specifically targeting the peripheral airways.

Advances in metered dose inhaler technology: formulation development

Pressurized metered dose inhalers (MDIs) are a long-standing method to treat diseases of the lung, such as asthma and chronic obstructive pulmonary disease. MDIs rely on the driving force of the propellant, which comprises the bulk of the MDI formulation, to atomize droplets containing drug and excipients, which ideally should deposit in the lungs. During the phase out of chlorofluorocarbon propellants and the introduction of more environmentally friendly hydrofluoroalkane propellants, many improvements were made to the methods of formulating for MDI drug delivery along with a greater understanding of formulation variables on product performance. This review presents a survey of challenges associated with formulating MDIs as solution or suspension products with one or more drugs, while considering the physicochemical properties of various excipients and how the addition of these excipients may impact overall product performance of the MDI. Propellants, volatile and nonvolatile cosolvents, surfactants, polymers, suspension stabilizers, and bulking agents are among the variety of excipients discussed in this review article. Furthermore, other formulation approaches, such as engineered excipient and drug-excipient particles, to deliver multiple drugs from a single MDI are also evaluated.

Advances in metered dose inhaler technology: formulation development

Pressurized metered dose inhalers (MDIs) are a long-standing method to treat diseases of the lung, such as asthma and chronic obstructive pulmonary disease. MDIs rely on the driving force of the propellant, which comprises the bulk of the MDI formulation, to atomize droplets containing drug and excipients, which ideally should deposit in the lungs. During the phase out of chlorofluorocarbon propellants and the introduction of more environmentally friendly hydrofluoroalkane propellants, many improvements were made to the methods of formulating for MDI drug delivery along with a greater understanding of formulation variables on product performance. This review presents a survey of challenges associated with formulating MDIs as solution or suspension products with one or more drugs, while considering the physicochemical properties of various excipients and how the addition of these excipients may impact overall product performance of the MDI. Propellants, volatile and nonvolatile cosolvents, surfactants, polymers, suspension stabilizers, and bulking agents are among the variety of excipients discussed in this review article. Furthermore, other formulation approaches, such as engineered excipient and drug-excipient particles, to deliver multiple drugs from a single MDI are also evaluated.

Factors affecting the stability and performance of ipratropium bromide; fenoterol hydrobromide pressurized-metered dose inhalers

The aim of the study was to investigate the factors affecting the stability and performance of ipratropium bromide and fenoterol hydrobromide in a pressurized-metered dose inhaler (pMDI). A factorial design was applied to investigate the effects of three parameters (propellant, water, and ethanol) on the performance of 27 designed formulations of a solution-based pMDI. The formulations that contained a hydrofluoroalkane (HFA) propellant lower than 72% v/v and an ethanol concentration higher than 27% v/v remained as clear solutions. Nine formulations that contained the HFA propellant higher than 74% v/v precipitated. The results indicated that it was not only the HFA propellant content of the formulations that was related to the formulation instability but also ethanol content. Only six formulations from the 18 formulations, that did not precipitate, produced drug contents that were within the acceptable range (80-120%). These six formulations generated aerosols with mass median aerodynamic diameters (MMAD) of approximately 2 μm with a fine particle fraction (FPF; particle size, <6.4 μm) between 45% and 52%. The MMAD and FPF did not change significantly after 6 months of storage (P > 0.05).

Inhaled corticosteroid and long-acting β2-agonist pharmacological profiles: effective asthma therapy in practice

Fixed-dose combinations of inhaled corticosteroids (ICSs) and long-acting β2-agonists (LABAs) have been used to manage asthma for several years. They are the preferred therapy option for patients who do not achieve optimal control of their asthma with low-dose ICS monotherapy. In Europe, four ICS/LABA products are commercially available for asthma maintenance therapy (fluticasone propionate/formoterol fumarate, fluticasone propionate/salmeterol xinafoate, budesonide/formoterol fumarate and beclometasone dipropionate/formoterol fumarate), and other combinations are likely to be developed over the next few years (e.g. mometasone/formoterol fumarate, fluticasone furoate/vilanterol, mometasone/indacaterol). Data from randomized, controlled, clinical trials do not demonstrate a clear overall efficacy difference among ICS/LABA combinations approved for asthma therapy. Conversely, pharmacological data indicate that there may be certain advantages to using one ICS or LABA over another because of the specific pharmacodynamic and pharmacokinetic profiles associated with particular treatments. This review article summarizes the pharmacological characteristics oft he various ICSs and LABAs available for the treatment of asthma, including the potential for ICS and LABA synergy, and gives an insight into the rationale for the development of the latest ICS/LABA combination approved for asthma maintenance therapy.

Lung penetration and patient adherence considerations in the management of asthma: role of extra-fine formulations

The mainstay of management in asthma is inhalation therapy at the target site, with direct delivery of the aerosolized drug into the airways to treat inflammation and relieve obstruction. Abundant evidence is available to support the concept that inflammatory and functional changes at the level of the most peripheral airways strongly contribute to the complexity and heterogeneous manifestations of asthma. It is now largely accepted that there is a wide range of clinical phenotypes of the disease, characterized primarily by small airways involvement. Thus, an appropriate diagnostic algorithm cannot exclude biological and functional assessment of the peripheral airways. Similarly, achievement of optimal control of the disease and appropriate management of specific phenotypes of asthma should be based on drugs (and delivery options) able to distribute uniformly along the bronchial tree and to reach the most peripheral airways. Products developed with the Modulite^® technology platform have been demonstrated to meet these aims. Recent real-life studies have shown clearly that extra-fine fixed-combination inhaled therapy provides better asthma control than non-extra-fine formulations, thus translating the activity of the drugs into greater effectiveness in clinical practice. We suggest that in patients with incomplete asthma control despite good lung function, involvement of the peripheral airways should always be suspected. When this is the case, treatments targeting both the large and small airways should be used to improve asthma control. Above all, it is emphasized that patient adherence with prescribed medications can contribute to clinical success, and clinicians should always be aware of the role played by patients themselves in determining the success or failure of treatment.

Novel cosuspension metered-dose inhalers for the combination therapy of chronic obstructive pulmonary disease and asthma

Pressurized metered dose inhaler is the most common inhaled dosage form, ideally suited for delivering the highly potent compounds that medicinal chemists typically discover for respiratory therapeutic targets. The clinical benefit of combination therapy for asthma and chronic obstructive pulmonary disease has been well established, and many of the new discovery candidates are likely to be studied in the clinic as combination drugs even at early stages of development. We present a novel pressurized metered dose inhaler formulation approach to enable consistent aerosol performance of a respiratory therapeutic whether it is emitted from a single-, double- or triple-therapy product. This should enable rapid nonclinical and clinical assessment whether alone or in combination with other drugs, without the challenge of in vitro performance dissimilarity across product types.

Modulite technology in the development of formoterol HFA pMDI: clinical evidence and future opportunities

This article is based on published safety and efficacy data on formoterol pressurized metered-dose inhalers (pMDIs) developed with the Modulite technology. This technology allows the development of ozone-friendly inhaled drugs that replace the same doses of chlorofluorocarbon (CFC)-formulated products and enables the attainment of new formulations with extra-fine particles and improved lung deposition. Clinical pharmacology, as well as clinical studies against comparators, have demonstrated that formoterol Modulite and the existing dry powder inhaler and CFC formoterol formulations have a similar pharmacokinetic profile, are clinically equivalent in bronchodilating effects and exhibit a similar potential for systemic side effects. Therefore, the Modulite formoterol hydrofluoroalkane-based formulation in extra-fine particles is a valuable therapeutic option for both patients and physicians in the management of asthma and chronic obstructive pulmonary disease.

In vitro drug delivery performance of a new budesonide/formoterol pressurized metered-dose inhaler

BACKGROUND

A combination of the corticosteroid budesonide and the long-acting beta2-adrenergic agonist formoterol is available in the United States in a single hydrofluoroalkane pressurized metered-dose inhaler (pMDI) for treatment of persistent asthma. The in vitro performance of the product, including delivered dose uniformity, aerodynamic particle size distribution, and dose proportionality, was evaluated.

METHODS

Both marketed formulations of the product were assessed (budesonide/formoterol 80/4.5 microg and 160/4.5 microg). Delivered dose was determined throughout the canister life using an automated dose delivery test method, and aerodynamic particle size distribution was evaluated using an Andersen Cascade Impactor-both in six batches of the product. Proportionality was assessed in 16 batches across three formulation strengths of budesonide, including a development formulation of 40/4.5 microg.

RESULTS

Budesonide/formoterol pMDI provided a consistent delivered dose, with a mean value within +/-15% of the label claim for both actives. All individual results were within +/-20% of label claim. Mean fine particle dose (dose fraction <4.7 microm) was 59 and 68% for budesonide and formoterol, respectively. Delivered dose of budesonide was proportional to labeled dose, and fine particle dose was slightly less than proportional. Changes in budesonide content did not affect formoterol dose.

CONCLUSIONS

Budesonide/formoterol pMDI provides a consistent delivered dose with an appropriate respirable fraction for therapeutic effectiveness. The product satisfies the performance requirements of current U.S. pharmacopeial and regulatory standards for pharmaceutical pMDI products.

Lung function and asthma control with beclomethasone and formoterol in a single inhaler

BACKGROUND

Lung deposition is crucial for asthma treatment. However, there is no study comparing the potential role of lung co-deposition of combination therapy (inhaled corticosteroid and long-acting beta2 agonist) in the same inhaler. In moderate to severe asthmatics, an extra-fine hydrofluoroalkane combination of beclomethasone dipropionate and formoterol given via a single pressurised metered-dose inhaler (pMDI) was compared with beclomethasone dipropionate chlorofluorocarbon (CFC) pMDI and formoterol dry powder inhaler (DPI) given via separate inhalers.

METHODS

In a double-blind, double-dummy, 24-week randomised clinical trial, 645 patients with moderate to severe asthma uncontrolled by regular treatment with inhaled corticosteroids received regular treatment with extra-fine fixed combination beclomethasone dipropionate 200 microg/formoterol 12 microg bid, or beclomethasone dipropionate (500 microg bid) via CFC pMDI and formoterol (12 microg bid) via DPI, or beclomethasone dipropionate (500 microg bid) via CFC pMDI. The primary outcome was morning peak expiratory flow (PEF). Secondary outcomes included lung function measured at clinic, asthma symptoms and control, exacerbations.

RESULTS

Beclomethasone dipropionate/formoterol combination via single inhaler or via separate inhalers improved morning PEF. However, the combination via single inhaler was more effective than given via separate inhalers for asthma control. Both combination treatments were superior to beclomethasone dipropionate alone in improving lung function and asthma control. All treatments were well tolerated.

INTERPRETATION

In patients with moderate to severe asthma, beclomethasone dipropionate/formoterol in a single inhaler was as effective as beclomethasone dipropionate plus formoterol and superior to beclomethasone dipropionate alone in improving lung function. For the first time with a single inhaler, beclomethasone dipropionate/formoterol was significantly superior to separate components for asthma control.

Advances in asthma and COPD management: delivering CFC-free inhaled therapy using Modulite technology

Inhaled corticosteroids (ICS) and long-acting beta-agonists (LABA) are currently used in the management of asthma and chronic obstructive pulmonary disease (COPD). Localized targeted delivery of these drugs into the lungs is achieved by means of two types of inhalation devices; pressurized metered-dose inhalers (pMDIs) and dry powder-inhalers (DPIs). For environmental reasons, the chlorofluorocarbon (CFC) propellants used in pMDIs are now being replaced by ozone friendly hydrofluoroalkanes (HFAs). These new generation HFA-based pMDIs, developed to provide effective lung deposition of the active moiety, have a favorable safety and tolerability profile. However, HFA-based re-formulation of LABAs and ICS for pMDIs presents particular technical difficulties, especially in terms of ensuring dose content uniformity. This review focuses on the technology and clinical efficacy of the HFA solution pMDIs using Modulite platform technology (Chiesi Farmaceutici S.p.A). Modulite technology allows the development of HFA solution formulations that can mimic the established CFC-based drug formulations on a microgram to microgram basis and provides formulations with novel particle size distributions that improve on existing delivery systems; by manipulation of aerosol clouds and particle size, the delivery of HFA-formulated drugs can be optimized to either achieve fine particle fractions and deposition patterns similar to established CFC-based drug formulations, thus facilitating the transition to new environment-friendly pMDIs in the clinical setting, or achieve finer drug particles able to penetrate deeper into the bronchi for targeted drug delivery as medical need may dictate. Long-term, multiple-dose clinical studies of Modulite formulations of beclomethasone dipropionate (BDP), budesonide and formoterol have been demonstrated to be therapeutically equivalent to their respective previously established CFC or DPI formulations. As a result, a number of Modulite pMDIs have either recently gained regulatory approval in several European countries, or have completed clinical trials and are in the regulatory submission phase. Availability, in pMDI form, of drugs like formoterol, ICSs, and ICS/LABA combinations, all central to the effective management of asthma and COPD, is therefore expected to impact positively in assuring the continued availability of vital treatment options to patients and physicians.